1. Field of the Invention
The present invention relates to testing devices and, particularly, to a testing device for multihole workpieces.
2. Description of Related Art
Multihole workpieces are widely used in many manufacturing industry. Multihole workpiece usually defines a great amount of holes therein. Referring to FIGS. 7 and 8, a multihole workpiece 10 has a plurality of holes 12 defined therein. The holes 12 are manufactured with many punches. However, since some punches tends to fail during the manufacturing process, some holes 12 are not often formed. As the holes 12 are very tinny, operators find it difficult to spot the uncompleted holes, which decrease the efficiency of the assembly process. Therefore, it is very important for the holes 12 in the multihole workpiece 10 to be tested.
Conventional detecting methods include a manual testing method and a non-contacting testing method. The manual testing method is that operators lower a needle into each hole of the workpiece so as to test whether the holes is through or not. The manual testing method is simple. However, when there are large numbers of holes, it is possible for the operator to miss the uncompleted holes. In addition, this testing process is time consuming, which affect the efficiency of the testing process. The non-contacting testing method can detect the uncompleted holes of multihole workpiece. However, the structure of the non-contacting testing device is complicated and large in volume. Therefore, it is difficult to move/relocate the non-contacting testing device. In addition, the non-contacting testing device is desired to work in a non-polluting testing environment to avoid components being contaminated by dusts. If the testing device works in a dusty environment, the testing reliability is low.
Therefore, a new testing device is desired in order to overcome the above-described shortcomings.